Abatacept for Rheumatoid Arthritis Refractory to Tumor Necrosis Factor α Inhibition

Abatacept is a recombinant fusion protein that modulates T-cell activation. In this trial in patients with rheumatoid arthritis who had an inadequate response to tumor necrosis factor a (TNF-a) inhibitors, 50.4 percent of these patients in the abatacept group had clinical improvement of at least 20 percent at six months, as compared with 19.5 percent of those in the placebo group. The incidence of serious infections was 2.3 percent in each group. In patients with rheumatoid arthritis who had an inadequate response to tumor necrosis factor α (TNF-α) inhibitors, 50.4 percent of patients in the abatacept group had clinical improvement of at least 20 percent at six months. Rheumatoid arthritis is a chronic disease that leads to inflammation and progressive joint damage. 1 Current therapies target the inflammatory consequences of autoimmune activation with the use of disease-modifying antirheumatic drugs (DMARDs) such as methotrexate and biologic DMARDs, which inhibit inflammatory cytokines such as tumor necrosis factor α (TNF-α). 2 Despite the efficacy of agents such as TNF-α inhibitors, a substantial proportion of patients have no response, 3 – 5 have an unsustained response, 6 or form antibodies against the drugs. 7 There are currently no clinically proven treatment options for patients with an inadequate response to anti–TNF-α therapy. Abatacept is the first in a new . . .